Data: Quarta-feira 14 de Dezembro de 2005

Hora: 14h30

Local: Colégio L.A. Verney, Anfiteatro I



RESUMO

In this work, we extend this model to normal fault configurations. Normal faults earthquakes occur in extensional regimes, and are knowned to produce fewer large earthquakes. Nevertheless, the very simple geometry of the stess field in such configurations allows us to constraint mechanical parameters with a good accuracy, with the aim of designing a more general model for the monitoring of seismic activity. A very complete catalogue of seismicity is used to search for AMR prior to the 5 large (M>6) normal fault earthquakes that struck Greece since 1980. The results are discussed in order to look for persistent patterns in the characteristics of the distribution of foreshocks. The issues discussed in this study are linked with the possibility of defining a regional stress field, the existence of vertical and lateral heterogeneities of the upper and middle crust, seismicity induced by fluids, quantification of earthquake activity, or the inclusion of seismogenic faults in the large scale tectonics of the region.

Although initially formulated in the hope to find a means of "predicting" earthquakes, the AMR models are now more modestly used to examine past seismicity with a "post-prediction" stategy, in order to give insights on particular problems of tectonics and earthquakes physics.